Inspection device and method for disposing magneto-optical crystal

Patent metadata

Field	Value
Publication number	US-10139370-B2
Application number	US-201515314657-A
Country	US
Kind code	B2
Filing date	Jun 2, 2015
Priority date	Jun 4, 2014
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

An inspection device includes a light source, an MO crystal disposed to face a semiconductor device (D), an object lens configured to concentrate the light output from the light source onto the MO crystal, a holder configured to hold the MO crystal, a flexible member interposed between the MO crystal and the holder, and an object lens drive unit configured to cause the MO crystal to contact the semiconductor device (D) by causing the holder to be moved in the optical axis direction of the object lens, wherein, when the MO crystal contacts the semiconductor device (D), the flexible member is bent, so that an incident plane is inclined in a range in which an inclination angle of the incident plane of the light in the MO crystal with respect to a plane orthogonal to the optical axis is less than or equal to an aperture angle.

First claim

The invention claimed is:

1. An inspection device comprising:
a light source configured to output light;
a magneto-optical crystal disposed to face a measurement object;
a lens configured to concentrate the light onto the magneto-optical crystal;
a holder configured to hold the magneto-optical crystal;
a flexible member interposed between the magneto-optical crystal and the holder; and
a drive configured to cause the magneto-optical crystal to contact the measurement object by moving the holder in an optical axis direction of the lens,
wherein the flexible member bends to enable an incident plane to incline in a range in which an inclination angle of the incident plane of the light in the magneto-optical crystal with respect to a plane orthogonal to the optical axis is equal to or less than an aperture angle of the lens when the magneto-optical crystal contacts with the measurement object, and
wherein the magneto-optical crystal has a reflective film on a surface in contact with the measurement object, reflecting a part of the light and transmitting a part of the light.

2. The inspection device according to claim 1 , wherein the flexible member is interposed between the holder and the magneto-optical crystal in the optical axis direction.

3. The inspection device according to claim 2 ,
wherein an opening through which the light from the light source is transmitted is formed in the holder, and
wherein the magneto-optical crystal is interposed within a region of the opening as viewed from the optical axis direction.

4. The inspection device according to claim 3 , wherein an opening through which the light is transmitted between the opening and the magneto-optical crystal is formed in the flexible member.

5. The inspection device according to claim 1 ,
wherein the holder is attached to the lens, and
wherein the driver moves the holder in the optical axis direction of the lens and causes the magneto-optical crystal to contact the measurement object by moving the lens in the optical axis direction.

6. The inspection device according to claim 1 , wherein the light is incoherent light.

7. The inspection device according to claim 1 , wherein a wavelength of the light is 1064 nm or more.

8. The inspection device according to claim 1 , wherein the flexible member has elasticity.

9. The inspection device according to claim 1 , further comprising:
an optical scanner, the optical scanner scanning light across a selected region on an incident plane of the magneto-optical crystal.

10. The inspection device according to claim 1 , wherein a modulated current is applied to the object, and lock-in detection is performed to detect measured light at a specific frequency.

11. The inspection device according to claim 1 , wherein the reflecting film is a material which reflects a wavelength for observing a change in the magnetic field and transmits a wavelength for observing the semiconductor device.

12. The inspection device according to claim 1 , wherein the reflecting film is a material which transmits and reflects light of a wavelength of 1064 nm or more.

13. A method of disposing a magneto-optical crystal facing a measurement object, wherein a holder holds the magneto-optical crystal via a flexible member, the method comprising:
disposing the magneto-optical crystal on an optical axis of an object lens;
causing the magneto-optical crystal to contact the measurement object by moving the holder in an optical axis direction of the object lens; and
inclining an incident plane in a range in which an inclination angle of the incident plane of the light in the magneto-optical crystal with respect to a plane orthogonal to the optical axis is equal to or less than an aperture angle of the object lens by bending the flexible member when the magneto-optical crystal contacts the measurement object,
wherein the magneto-optical crystal has a reflective film on a surface in contact with the measurement object, reflecting a part of the light and transmitting a part of the light.

Assignees

• Hamamatsu Photonics Kk

Inventors

• Nakamura Tomonori

Classifications

• G01R31/28

  Testing of electronic circuits, e.g. by signal tracer ({EMC, EMP or similar testing of electronic circuits G01R31/002;} testing for short-circuits, discontinuities, leakage or incorrect line connection G01R31/50; checking computers {or computer components} G06F11/00; checking static stores for correct operation G11C29/00 {; testing receivers or transmitters of transmission systems H04B17/00}) · CPC title

• G01R33/032

  using magneto-optic devices, e.g. Faraday {or Cotton-Mouton effect} · CPC title

• G01R31/26

  Testing of individual semiconductor devices (testing of photovoltaic devices H02S50/10; testing or measuring during manufacture or treatment {H10P74/00}) · CPC title

• G01N27/72 Primary

  by investigating magnetic variables · CPC title

• G01R31/308

  using non-ionising electromagnetic radiation, e.g. optical radiation {(investigating or analysing materials by the use of optical means G01N21/00; image analysis G06T7/00)} · CPC title